Thread: Valve Testers
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Old 15th Feb 2019, 7:21 pm   #30
Bazz4CQJ
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Default Re: Valve Testers

Quote:
Originally Posted by woodchips View Post
Surely emission measurements can be easily checked, even for valves without an manufacturers' data?

Assuming a US, European valve then the cathode emission is simply limited by the area of the cathode and its temperature.
Well, certainly with indirectly heated valves, which have a cathode, some valves will glow nicely and look fine, but have quite poor emission. Temperature alone is not the key issue; the physics and chemistry of the cathode material is critical and complex. There are volumes of technical papers written about cathode behaviour.

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